797 resultados para Young volunteers in community development.
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The existence of at least three isoforms of Na(+)-K(+)-ATPase in adult brain tissues [alpha 1, kidney type; alpha 2 [or alpha(+)]; alpha 3] suggests that these genes might be regulated in a cell-specific and time-dependent manner during development. We have studied this question in serum-free aggregating cell cultures of mechanically dissociated rat fetal telencephalon. At the protein level, the relative rate of synthesis of the pool of alpha 1-, alpha 2-, and alpha 3-subunits increased approximately twofold over 15 days of culture, leading to a marked increase in the immunochemical pool of alpha-subunits as measured by a panspecific polyclonal antibody. Concomitantly, Na(+)-K(+)-ATPase enzyme-specific activity increased three- (lower forebrain) to sixfold (upper forebrain). The transcripts of all three alpha-isoforms and beta-subunit were detected in vitro in similar proportion to the level observed in vivo. alpha 3-mRNA (3.7 kb) was more abundant than alpha 1 (3.7 kb) or alpha 2 (5.3 and 3.4 kb). Cytosine arabinoside (0.4 microM) and cholera toxin (0.1 microM) were used to selectively eliminate glial cells or neurons, respectively. It was found that alpha 2-mRNA is predominantly transcribed in glial cell cultures, whereas alpha 3- and beta 1-mRNA (2.7, 2.3, and 1.8 kb) are predominant in neuronal cultures.
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The following paper introduces a new approach to the analysis of offensive game in football. Therefore, the main aim of this study was to create an instrument for collecting information for the analysis of offensive action and interactions game. The observation instrument that was used to accomplish the main objective of this work consists of a combination of format fields (FC) and systems of categories (SC). This methodology is a particular strategy of the scientific method that has as an objective to analyse the perceptible behaviour that occurs in habitual contexts, allowing them to be formally recorded and quantified and using an ad hoc instrument in order to obtain a behaviour systematic registration that, since they have been transformed in quantitative data with the necessary reliability and validity determined level, will allow analysis of the relations between these behaviours. The codifications undertaken to date in various games of football have shown that it serves the purposes for which it was developed, allowing more research into the offensive game methods in football.
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The focus of my PhD research was the concept of modularity. In the last 15 years, modularity has become a classic term in different fields of biology. On the conceptual level, a module is a set of interacting elements that remain mostly independent from the elements outside of the module. I used modular analysis techniques to study gene expression evolution in vertebrates. In particular, I identified ``natural'' modules of gene expression in mouse and human, and I showed that expression of organ-specific and system-specific genes tends to be conserved between such distance vertebrates as mammals and fishes. Also with a modular approach, I studied patterns of developmental constraints on transcriptome evolution. I showed that none of the two commonly accepted models of the evolution of embryonic development (``evo-devo'') are exclusively valid. In particular, I found that the conservation of the sequences of regulatory regions is highest during mid-development of zebrafish, and thus it supports the ``hourglass model''. In contrast, events of gene duplication and new gene introduction are most rare in early development, which supports the ``early conservation model''. In addition to the biological insights on transcriptome evolution, I have also discussed in detail the advantages of modular approaches in large-scale data analysis. Moreover, I re-analyzed several studies (published in high-ranking journals), and showed that their conclusions do not hold out under a detailed analysis. This demonstrates that complex analysis of high-throughput data requires a co-operation between biologists, bioinformaticians, and statisticians.
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Ectodysplasin (Eda), a member of the tumor necrosis factor (Tnf) family, regulates skin appendage morphogenesis via its receptor Edar and transcription factor NF-κB. In humans, inactivating mutations in the Eda pathway components lead to hypohidrotic ectodermal dysplasia (HED), a syndrome characterized by sparse hair, tooth abnormalities, and defects in several cutaneous glands. A corresponding phenotype is observed in Eda-null mice, where failure in the initiation of the first wave of hair follicle development is a hallmark of HED pathogenesis. In an attempt to discover immediate target genes of the Eda/NF-κB pathway, we performed microarray profiling of genes differentially expressed in embryonic skin explants after a short exposure to recombinant Fc-Eda protein. Upregulated genes included components of the Wnt, fibroblast growth factor, transforming growth factor-β, Tnf, and epidermal growth factor families, indicating that Eda modulates multiple signaling pathways implicated in skin appendage development. Surprisingly, we identified two ligands of the chemokine receptor cxcR3, cxcl10 and cxcl11, as new hair-specific transcriptional targets of Eda. Deficiency in cxcR3 resulted in decreased primary hair follicle density but otherwise normal hair development, indicating that chemokine signaling influences the patterning of primary hair placodes only.
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Background: C-reactive protein (CRP) is associated with risk of coronary heart disease (CHD). Whether CRP is causally associated with CHD or merely a marker of underlying atherosclerosis is uncertain. Methods: We used a Mendelian randomisation design to investigate the causal relationship of CRP with CHD. We identified three genetic variants in the CRP locus (rs7553007, rs1130864 and rs1205) which influence CRP levels. We tested the three SNPs for association with CHD amongst 28,112 CHD cases and 100,823 controls. We then compared the observed relationship between the SNPs and CHD, with that predicted from the association of SNPs with CRP levels, and of CRP levels with CHD. Results: SNPs in the CRP locus were not associated with CHD: rs7553007, OR 0.98 (95% CI, 0.94-1.01); rs1130864, OR 1.00 (95% CI, 0.86-1.15); rs1205, OR 1.03 (95% CI, 0.99-1.07); combined OR for all three SNPs, 1.00 (95% CI, 0.97-1.02), per 20% lower CRP (figure). In contrast, the predicted OR for CHD from a 20% lower CRP level is 0.94 (95% CI, 0.94- 0.95), based on meta-analysis of observational studies. Conclusions: Though CRP variants are associated with CRP levels, and CRP levels with risk of CHD, we observed that CRP variants are not associated with CHD risk. Our Mendelian randomisation experiment strongly argues against a causal association of CRP with CHD.
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Audit report on the Community Development Block Grants program for the City of Bedford, Iowa for the year ended June 30, 2014
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PURPOSE OF REVIEW: In the present review, we will provide the scientific rationale for applying systems biology to the development of vaccines and particularly HIV vaccines, the predictive power of systems biology on the vaccine immunological profile, the correlation between systems biology and the immunological functional profiles of different candidate vaccines, and the value of systems biology in the selection process of identifying the best-in-class candidate vaccines and in the decision process to move into in-vivo evaluation in clinical trials. RECENT FINDINGS: Systems biology has been recently applied to the characterization of the protective yellow fever vaccine YF17D and of seasonal flu vaccines. This has been instrumental in the identification of the components of the immune response that need to be stimulated by the vaccine in order to generate protective immunity. It is worth noting that a systems biology approach is currently being performed to identify correlates of immune protection of the RV144 Thai vaccine, the only known vaccine that showed modest protection against HIV reacquisition. SUMMARY: Systems biology represents a novel and powerful approach to predict the vaccine immunological profile, to identify the protective components of the immune response, and to help in the selection process of the best-in-class vaccines to move into clinical development.
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ABSTRACT: BACKGROUND: Current tools for analgesia are often only partially successful, thus investigations of new targets for pain therapy stimulate great interest. Consequent to peripheral nerve injury, c-Jun N-terminal kinase (JNK) activity in cells of the dorsal root ganglia (DRGs) and spinal cord is involved in triggering neuropathic pain. However, the relative contribution of distinct JNK isoforms is unclear. Using knockout mice for single isoforms, and blockade of JNK activity by a peptide inhibitor, we have used behavioral tests to analyze the contribution of JNK in the development of neuropathic pain after unilateral sciatic nerve transection. In addition, immunohistochemical labelling for the growth associated protein (GAP)-43 and Calcitonin Gene Related Peptide (CGRP) in DRGs was used to relate injury related compensatory growth to altered sensory function. RESULTS: Peripheral nerve injury produced pain-related behavior on the ipsilateral hindpaw, accompanied by an increase in the percentage of GAP43-immunoreactive (IR) neurons and a decrease in the percentage of CGRP-IR neurons in the lumbar DRGs. The JNK inhibitor, D-JNKI-1, successfully modulated the effects of the sciatic nerve transection. The onset of neuropathic pain was not prevented by the deletion of a single JNK isoform, leading us to conclude that all JNK isoforms collectively contribute to maintain neuropathy. Autotomy behavior, typically induced by sciatic nerve axotomy, was absent in both the JNK1 and JNK3 knockout mice. CONCLUSIONS: JNK signaling plays an important role in regulating pain threshold: the inhibition of all of the JNK isoforms prevents the onset of neuropathic pain, while the deletion of a single splice JNK isoform mitigates established sensory abnormalities. JNK inactivation also has an effect on axonal sprouting following peripheral nerve injury.
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The appearance of immunoreactive alpha-melanotropin (alpha-MSH) and adrenocorticotropin (ACTH) during development was studied in 3 areas of the rat brain--cerebral hemispheres, midbrain and hindbrain--from embryonic day (ED) 13-14 until day 21 postnatally. The alpha-MSH content in vivo was always highest in the midbrain; a peak content at birth was followed by a transient decline and a later, higher plateau from postnatal day 7 onwards. The alpha-MSH content in the cerebral hemispheres rose progressively after birth reaching a peak at day 21. Values in the hindbrain rose at day 3 and changed relatively sue taken at ED 15-16 showed a gradual increase in alpha-MSH content over the 20 days. The alpha-MSH content of hindbrain cultures remained at constant low levels, while no alpha-MSH was detectable in cerebral hemisphere cultures. ACTH appeared in vivo earlier than alpha-MSH and was detectable in embryonic brains at ED 13-14. A transient rise was seen at ED 17-18 and major peaks at birth, day 2 and day 3, in the midbrain, hemispheres and hindbrain, respectively. In vitro, the ACTH content increased in all brain regions during the first 5 days in culture and showed no further change thereafter. Comparisons of the in vivo and in vitro development of alpha-MSH and ACTH demonstrate that (i) these two peptide systems are independent in respect to their localization and time of appearance; (ii) they undergo maturation both in vivo and in vitro; (iii) epigenetic factors, such as interactions with other neurotransmitter systems may modulate the developmental pattern of these two peptides.
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Résumé L'influence des hormones reproductives sur le développement du cancer du sein a été établie au travers de nombreuse études épidémiologiques. Nous avons précédemment démontré que le gène Wnt-4 est un médiateur essentiel de la progestérone dans le développement lobulo-alvéolaire de l'épithélium mammaire. De plus, le rôle de la voie de signalisation Wnt dans la tumorigénèse de la glande mammaire mutine est largement établi. Pour comprendre sa fonction dans le cancer du sein, nous avons activée cette voie en surexprimant le gène Wnt-1 dans des cellules épithéliales primaires de sein, au moyen d'un rétrovirus. Ceci a conduit à la transformation oncogénique de ces cellules et à l'obtention d'un modèle de carcinogénèse du sein dénommé Wnt-1 HMEC. L'analyse de l'expression des gènes induits par la surexpression de Wnt-1 dans ces cellules, a permis d'identifier les gènes BMP4 et 7. Alors que des analyses de RT-PCR ont montré leur forte expression dans les cellules Wnt-1-HMECs, la présence d'une grande quantité de la protéine BMP7 a été constatée dans les tumeurs dérivées de ces cellules. L'importante phosphorylation des Smad 1, 5, S dans les Wnt-1 HMECs indique l'activation de la voie BMP, possiblement due à la stimulation ce celle-ci par BMP7. L'activation de la voie Wnt par la ß-Caténine, conduit à la transcription de BMP7, identifiant ainsi ce gène comme un gène cible de la voie canonique. La pertinence de nos observations a par ailleurs été confirmée par le fait que BMP7 est surexprimé dans les tumeurs de seins humains. Afin d'élucider la fonction de la voie BMP dans le sein, nous avons utilisé le modèle mutin. L'expression du gène BMP7 dans les souris transgéniques MMTV Wnt-1 s'est avérée élevée, démontrant qu'il est aussi un gène cible de la voie Wnt in-vivo. L'expression de l'ARN messager .codant pour la protéine BMP7 est induite lors du développement lobulo-alvéolaire, qui se fait sous l'influence de la progestérone et de Wnt-4. Ensemble, ces observations corroborent le fait qu'une stimulation avec de la progestérone suffit à induire la transcription du gène dans les 24h. Nos résultats coïncident d'autre part avec le fait que BMP7 est exprimé dans la couche myoépithéliale de l'épithélium où la voie Wnt est activée. L'analyse de souris reportrices de l'activité de la voie BMP, suggère une activation dans la couche luminale de l'épithélium durant tout le développement de la glande mammaire. Curieusement, cette même voie est active dans le mésenchyme lors de la mammogénèse embryonnaire. Finalement, nos analyses d'immunofluorescence démontrent la capacité de prolifération des cellules ayant activé BMP, ainsi que leur nette ségrégation d'avec les cellules exprimant le récepteur à la progestérone. Nos résultats démontrent que le gène BMP7 est un gène cible de la voie Wnt canonique dans le sein. Son expression dans la couche myoépitheliale est induite par Wnt-4, lui-même sécrété par les cellules luminales sensibles à la progestérone. La sécrétion de la protéine BMP7 conduit finalement à l'activation de la voie BMP dans les cellules négatives pour le récepteur à la progestérone. Abstract Epidemiological studies highlight the repetitive exposure to circulating progesterone as a major risk in the development of breast cancer. Work in our laboratory showed that Wnt-4 is an essential mediator of progesterone-driven side-branch formation, while Wnt signaling has long been established as strongly oncogenic in the mouse mammary gland. To address the role of Wnt in breast tumorigenesis we activated the pathway in primary human breast epithelial cells by means of refroviral Wnt-1 expression. This resulted in a Wnt1-induced breast carcinogenesis model, being referred to as Wnt-1-HMECs. Gene expression profiling revealed the Bone Morphogenetic Protein 4 and 7 (BMP4 and 7) a mong the most upregulated gene by ectopic Wnt-1 expression in primary HMECs. RT-PCR analysis confirmed elevated BMP4 and 7 mRNA levels in Wnt-1-infected HMECs, as well as strong BMP7 expression in the tumors derived from these cells. Smad 1, 5, 8 phosphorylation was high in Wnt-1HMECs whereas below detection limit in primary HMECs suggesting that the increased expression of BMP-7 results in activation of downstream signaling. Ectopic expressíon of a stabilized form of ßcatenin in primary HMECs resulted in increased transcription of BMP-7 suggesting that it is a target of canonical Wnt signaling. The clinical relevance of our observations was confirmed by the finding of BMP7 being upregulated in human breast tumor samples. To elucidate the role of BMP ligands in the breast in-vivo, we made use of the mouse model. Expression of the BMP7 gene was found to be increased in MMTV-Wnt-1 transgenic animals, suggesting that BMP7 may also be a Wnt 1 target gene in vivo. Expression of BMP7 was upregulated in mid-pregnancy which coincides with progesterone/Wnt induced side branching. BMP7 was induced within 24 hours by progesterone. Consistent with it being a target of canonical Wnt signaling, we demonstrated preferential expression of this ligand in the myoepithelial cells, the target cells of Wnt signals. In-vivo analysis of BMP signaling using a reporter mouse revealed the activation of the pathway in the luminal layer of the epithelium throughout postnatal development. Interestingly, during embryonic mammogenesis the pathway was found to be active in the mesenchyme. Immunofluorescence studies demonstrated that cells with BMP activity can proliferate. They also revealed a clear segregation between progesterone receptor positive cells and cells with active BMP signaling. Together our observations suggest that BMP-7 is a canonical Wnt signaling target both in HMECs and in the mouse mammary gland in-vivo. It is expressed in the myoepithelium possibly in response to Wnt-4, which is secreted by steroid receptor positive cells in response to progesterone. BMP-7 in turn may impinge on lumina) epithelial cells and activate BMP signaling in PR negative cells.
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Large slope failures in fractured rocks are often controlled by the combination of pre-existing tectonic fracturing and brittle failure propagation in the intact rock mass during the pre-failure phase. This study focuses on the influence of fold-related fractures and of post-folding fractures on slope instabilities with emphasis on Turtle Mountain, located in SW Alberta (Canada). The structural features of Turtle Mountain, especially to the south of the 1903 Frank Slide, were investigated using a high-resolution digital elevation model combined with a detailed field survey. These investigations allowed the identification of six main discontinuity sets influencing the slope instability and surface morphology. According to the different deformation phases affecting the area, the potential origin of the detected fractures was assessed. Three discontinuity sets are correlated with the folding phase and the others with post-folding movements. In order to characterize the rock mass quality in the different portions of the Turtle Mountain anticline, the geological strength index (GSI) has been estimated. The GSI results show a decrease in rock mass quality approaching the fold hinge area due to higher fracture persistence and higher weathering. These observations allow us to propose a model for the potential failure mechanisms related to fold structures.
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Early ocular development is controlled by a complex network of transcription factors, cell cycle regulators, and diffusible signalling molecules. Together, these molecules regulate cell proliferation and apoptosis, and specify retinal fate. NKX5-3 is a homeobox transcription factor implicated in eye development. The analysis of the 5'-flanking region of the mouse Nkx5-3 gene revealed a predicted TATA-less promoter sequence between -416 and -166 of the translation start site. To functionally characterise Nkx5-3 promoter activity, serial deletions of the promoter sequence were introduced in pGL-3 basic vector and promoter activity of these 5'- and 3'-deleted constructions was tested in HeLa and CHO cells. Transactivation assays identified a region between -350 and -296 exhibiting promoter-like activity. Combined analysis by deletions and point mutations showed that this sequence, containing multiple Sp1 binding sites was necessary to promote transcriptional activity. Binding of Sp1 to this region was confirmed by electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation, using an antibody specific for Sp1. Altogether, these results demonstrated that the immediate upstream region of Nkx5-3 gene possessed a strong intrinsic promoter activity in vitro, suggesting a potential role in Nkx5-3 transcription in vivo.
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Current therapeutic strategies against glioblastoma (GBM) have failed to prevent disease progression and recurrence effectively. The part played by molecular imaging (MI) in the development of novel therapies has gained increasing traction in recent years. For the first time, using expertise from an integrated multidisciplinary group of authors, herein we present a comprehensive evaluation of state-of-the-art GBM imaging and explore how advances facilitate the emergence of new treatment options. We propose a novel next-generation treatment paradigm based on the targeting of multiple hallmarks of cancer evolution that will heavily rely on MI.